Aspartate receptor

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Tar ligand binding domain homologue
Ligand binding domain aspartate receptor.png
Ribbon diagram of the S. typhimurium aspartate receptor ligand binding domain[1]
Identifiers
Symbol TarH
Pfam PF02203
InterPro IPR003122
SMART TarH
SCOP 1lih
SUPERFAMILY 1lih

The aspartate receptor, Tar, is a member of a family of transmembrane receptors that mediate chemotactic response in certain enteric bacteria, such as Salmonella typhimurium and Escherichia coli.[2] These methyl-accepting chemotaxis receptors are one of the first components in the sensory excitation and adaptation responses in bacteria, which act to alter swimming behaviour upon detection of specific chemicals. The aspartate receptor mediates movement towards the attractants aspartate and maltose, and away from the repellents nickel and cobalt. There are many different types of bacterial 60 kDa transmembrane receptors, which share similar topology and signalling mechanisms. They possess three domains: a periplasmic ligand-binding domain, two transmembrane segments, and a cytoplasmic domain. The structure of the ligand-binding domain comprises a closed or partly opened, four-helical bundle with a left-handed twist. The difference in the sequence of the ligand-binding domain between receptors reflects the different ligand specificities. Binding of the ligand causes a conformational change that is transmitted across the membrane to the cytoplasmic activation domain.[3]

References[edit]

  1. ^ PDB 1VLT; Yeh JI, Biemann HP, Privé GG, Pandit J, Koshland DE Jr, and Kim SH (1996). "High-resolution structures of the ligand binding domain of the wild-type bacterial aspartate receptor". J Mol Biol 262: 186–201. doi:10.1006/jmbi.1996.0507. PMID 8831788. ; rendered with PyMOL
  2. ^ Kim SH, Prive GG, Pandit J, Koshland DE, Yeh JI, Biemann HP (1996). "High-resolution structures of the ligand binding domain of the wild-type bacterial aspartate receptor". J. Mol. Biol. 262 (2): 186–201. doi:10.1006/jmbi.1996.0507. PMID 8831788. 
  3. ^ Koshland DE, Yu EW (2001). "Propagating conformational changes over long (and short) distances in proteins". Proc. Natl. Acad. Sci. U.S.A. 98 (17): 9517–9520. doi:10.1073/pnas.161239298. PMC 55484. PMID 11504940. 

This article incorporates text from the public domain Pfam and InterPro IPR003122